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Help in vectors

I don’t get how to solve it, do I just do A+B=C and work accordingly?

Three vectors are given by A = 2.0ex +3.0ey , B = 1.0ex +5.0ey , and C = −1.0ex +3.0ey . Find constants c1 and c2 such that c1A + c2B = C.
Original post by studentzz123
I don’t get how to solve it, do I just do A+B=C and work accordingly?

Three vectors are given by A = 2.0ex +3.0ey , B = 1.0ex +5.0ey , and C = −1.0ex +3.0ey . Find constants c1 and c2 such that c1A + c2B = C.

Write c1A+c2B=C. This will give you two equations (one for each of the x and y components) in two unknowns (c1, c2), which you can then solve for.
Original post by RogerOxon
Write c1A+c2B=C. This will give you two equations (one for each of the x and y components) in two unknowns (c1, c2), which you can then solve for.

That gives me c1(2ex + 3ey) + c2(1ex + 5ey) = -ex +3ey

I think I got it c1= -8/7 and c2= 9/7
(edited 4 years ago)
Original post by studentzz123
That gives me c1(2ex + 3ey) + c2(1ex + 5ey) = -ex +3ey

I think I got it c1= -8/7 and c2= 9/7

I've not checked your answers. Have you? If not, plug those numbers into the original equation, and check that they satisfy it.

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